Which, if any, of the following statements about electric field lines is/are true? a. the electric field is always perpendicular to the surface outside of a conductor.
b. if an electron were placed on an electric field line, it would move in a direction perpendicular to the field.
c. electric field lines originate on positive charge and terminate on negative charge.
d. it is possible for two electric field lines to cross each other.
e. if an electron and a positron were in the presence of a very strong electric field, they would move away from each other.
f. it is not possible for the electric field to ever be zero.
g. if a proton were placed on an electric field line, it would move in a direction anti-parallel to the field.

The electric field is always perpendicular to the surface outside of a conductor. TRUE

 If an electron were placed on an electric field line, it would move in a direction perpendicular to the field. FALSE, it would move in an anti-parallel direction because its charge is negative 
 
Electric field lines originate on positive charge and terminate on negative charge. TRUE ; but they can also go to infinity 
 
It is possible for two electric field lines to cross each other.
 Usually FALSE; though technically possible at special points where field is zero. 
 
If an electron and a positron were in the presence of a very strong electric field, they would move away from each other.
 TRUE; one is positive, and one is negative. If the field is strong enough, the action of the field will overcome the mutual attraction between them 
 
It is not possible for the electric field to ever be zero. FALSE: it IS possible, inside a conductor for instance
   
If a proton were placed on an electric field line, it would move in a direction anti-parallel to the field.
 FALSE: being positive, it would move in the SAME direction as the fieldic 

The answer should be a.